Automatic indicator or thermoscopic signal for heated tools and vessels.



Nol 8844973. PATENTBD APR.14,'1908.

` J. I. AYER. j j i AUTOMATIGLINDIGATOR- 0R THBBMOSGOPIG'SIGNAL FOR HEATED TooLs' ANDjVBssBLs.

APPLI'UATIQN FILED un 18.1007.

gmm@ @Hof/nego UNITED OFFICE.

JAMES l. AYER, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOR TO SIMPLEX ELEQTRIL` HEATING COMPANY, O'F BOSTON. MASSACHUSETTS, A CORPORATION OF MASSACHU- SETTS.

AUTOMATIC INDICATOR OR THERMOSCOPIC SIGNAL FOR HEATED TOOLS AND VESSELS.

Specification of Letters Patent.

Patented April 14, 1,908,

Application filed May 16, 1907, Serial N o. 374,067.

To all whom it lmay concern;

Be it known that l, JAMES I. AYER., a citizen of the United States, residing at Cam-A bridge, in the county of Middlesex-and State of Massachusetts, have invented an Improvement in Automatic Indicators' or Thermoscopic Signals for Heated Tools and Vessels,

of whichthe following description, in con-KV von the other hand, the operator is often'annoyed to find the article still cold, when he or she had vsupposed the current was on or heat had otherwise long` since been applied, where as in fact it had not been applied.

Accordingly my present invention provides a heat retaining, signal -protecting, thermosco ic signal-lever, or mechanicall displayed ut heat operated signal or indlcator, which automatically gives notice whenever the desired temperature is present in the tool, vessel or other article.

Referring to the drawings, in which I have shown one out of many contemplated embodiments of my invention, Figure 1 is a side elevation of my invention applied to a flatiron; Fig. 2 is a plan View thereof; and Fig. 3.

is a sectional detail.

For convenience of explanation, I have illustrated my signal or notice-giver in lconnection with a usual latiron, comprising a base 1, 2, and handle 3, the part 1 containln the usual electric resistance wires as usua for heating the tool. While my signaling device'may be located accordingto convenience or reference, l prefer to place it conspicuous y at the front and yet sheltered, and therefore I have deflected the front handlesupport at 4 and beneath this protector is a heat-transmission and retention box or housing 5, open at the top, in which is pivoted at with heat.

6 a signal lever 7, preferably having a boss or lifting lug 8 close to the fulcrum 6 to be engaged by the thermal lifter or actuator 9. The latter consists of two` strips 10 and 11 of dissimilarmetals soldered or otherwise secured flat upon each other lengthwise, in well-known manner, as in heat gages, watch balances,'etc., the lower strip or bottom part of the-laminas or laminated actuator 9 having the higher coefficient of expansion, This actuator 9 is made fast at 12 to a block 13 at the rear end of the box and projects forward in pushing or lifting contact with the signal lever 7. The latter may have a ballshaped head or other striking display art, being shown as provided with bright co ored disks 14, 15 set at right angles to eachother.

to its dotted position Fig. 3, and as shownin Fig. 1, thereby giving visual' notice that the iron is properly heated and ready for work. The construction shown'is'such that only a small upward movement ofthe laminar actuator 9 is suicient to force the signal lever 7 from its concealed horizontal osition to its upright displayed osition. is provides at a glance a vls'ua signal showing that the iron is actually lin service or provided so long as the temperature of the iron continues at or above the predetermined mi-ni' mum oint, which wasnecessary rst to raise t e lever to its ,vertical position. stop-part or lug 16 on the housing 1s 1n positionto prevent the lever 7 from rising beyond' f its dotted line position Fig. 3, so that 1t can The signal-lever remains raised vibration when' the laminated,l mem er has been curved by the action of the heat'into its" dotted line position, Fig. 3. When thus curved, the extremity of its movable end abuts against4 the face of the boss 8 .and

presses the lever 7 in non-vibrating or nonmovabie position against the stop 16, so that, as the flat-iron is shoved rapidly back and forth in the' process of ironing, the signal lever will not vibrate or rattle.

The casing or box coperates in maintaining normal temperature conditions about the signal actuator by preventing cooling air currents from reducing its temperature, and hence gives to the signal certainty of position and definiteness of results, while also serving as a protecting receptacle for the lever when lying parallel to'the laminar actuator.

As already intimated, there is a wide variety of shapes and arran ements in which my invention may be e'mbo ied. The actual movement of the signal serves to attract the eye'more deiinitely than the less obtrusive g ow of the lamp in my 1patent before mentioned and moreover ren( ers the signal available in connection with articles which are heated otherwisel than by electricity; and this feature of providing movement may be availed of for securing still further conspicuity, as by closing a circuit and iightin the signal when raised. My patented signal above mentioned shows simply whether the current is on or off, whereas the present signal shows whether -the iron is o erativeiy heated or not. It fiaunts its signa when the workin heat is attained. It will be understood t at the greatest precision and sensitiveness are secured, according to the length of the laminar actuator, the proporing lengthwise over the same when the iatter is cold, extending from one end at said pivot to the opposite free swinging end adjacent the fast end of the lifter, the free end of the lifter engaging said lever close to the pivot, to swing the leverv from said overlying iorizontai position to a raised vertical position.

2. The combination with an article of the kind described, having a portion to be heated, of a laminated member fast at one end and arranged to move upwardi at its other end when heated, and a signal liever pivoted close to said movable end and normally lying lengthwise over said laminated member when the latter is cold, said lever being rovided adjacent its pivot with a lifting boss projecting against the laminated member, the extreme end of the laminated member extending when cold between the pivot of the lever and said boss.

3. The combination with an article of the kind described, having a portion to be heated, of a laminated member fast at one end and arranged to curve u )wardiy at its other end when heated, a signa lever pivoted close to the latter end and overlying said member lengthwise, thefree moving end of the signal lever normali resting over the fixed end of the laminate member and the movable end of the laminated member normally resting close tothe pivot of the signal lever, a fixed stop against which the signal lever is moved when indicating maxilnum heat, said signal lever having a boss close to its pivot facing toward the laminated member, and the iatter having such a length that when extended and curved by the action of the heat its end will engage against said boss and hold the lever against said stop.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

JAS. I. AYER.

Witnesses:

E. B. STnB'aINs, FRANK A. iiEA. 

